Do low cortisol levels cause loss of morning erections, or is this phenomenon limited to high cortisol states?

Morning Erections and Cortisol Levels

Morning erections are lost with low cortisol (adrenal insufficiency), not high cortisol states. The evidence demonstrates that glucocorticoid and mineralocorticoid deficiency in adrenal insufficiency causes reversible sexual dysfunction, including erectile dysfunction, which improves after hormone replacement therapy 1.

Evidence for Low Cortisol Causing Sexual Dysfunction

• A prospective study of 12 men with newly diagnosed autoimmune Addison's disease (primary adrenal insufficiency) found significantly impaired erectile function, orgasmic function, sexual desire, intercourse satisfaction, and overall sexual satisfaction at baseline, all of which improved significantly after 2 months of gluco- and mineralocorticoid replacement therapy 1.

• The improvement in erectile function correlated positively with increases in serum cortisol and urinary free cortisol, and inversely with normalization of plasma renin activity (a marker of mineralocorticoid deficiency) 1.

• Multiple regression analysis confirmed that cortisol and aldosterone deficiency play an important role in the genesis of erectile dysfunction in adrenal insufficiency, though the exact mechanism remains unclear 1.

Why High Cortisol Does Not Cause Loss of Morning Erections

• Cushing's syndrome (chronic cortisol excess) presents with characteristic features including facial plethora, easy bruising, purple striae, hyperglycemia, hypertension, and central obesity, but loss of morning erections is not a recognized feature of this condition 2, 3.

• The physiological control of the hypothalamic-pituitary-adrenal axis involves cortisol negative feedback on ACTH secretion, but this mechanism does not directly impair erectile function 3.

Clinical Implications

• Morning erectile dysfunction in the context of other symptoms such as fatigue (50-95% of cases), nausea and vomiting (20-62%), weight loss (43-73%), orthostatic hypotension, or salt craving should prompt evaluation for adrenal insufficiency 4, 5.

• Obtain early morning (8 AM) paired cortisol and ACTH measurements as the first-line diagnostic test 5, 6, 4.

• Morning cortisol <250 nmol/L (<9 µg/dL) with elevated ACTH indicates primary adrenal insufficiency, while low cortisol with low or inappropriately normal ACTH indicates secondary adrenal insufficiency 5, 6, 4.

• If morning cortisol is indeterminate (140-500 nmol/L or 5-18 µg/dL), proceed with ACTH stimulation testing using 0.25 mg cosyntropin, with peak cortisol <500 nmol/L (<18 µg/dL) at 30 or 60 minutes confirming adrenal insufficiency 5, 6.

Treatment and Expected Recovery

• Initiate hydrocortisone 15-25 mg daily in divided doses (typically 10 mg at 7 AM, 5 mg at noon, 2.5-5 mg at 4 PM) for confirmed adrenal insufficiency 5, 6, 4.

• Add fludrocortisone 0.05-0.1 mg daily for primary adrenal insufficiency to replace mineralocorticoid deficiency 5, 6, 4.

• Sexual function, including morning erections, should improve within 2 months of initiating appropriate hormone replacement therapy 1.

• All patients require education on stress dosing (doubling or tripling doses during illness), a medical alert bracelet, and an emergency injectable hydrocortisone 100 mg IM kit 5, 6, 4.

Critical Pitfall to Avoid

• Never delay treatment of suspected acute adrenal crisis for diagnostic testing—if a patient presents with unexplained hypotension, collapse, severe vomiting, or altered mental status, immediately administer 100 mg IV hydrocortisone and 0.9% saline infusion at 1 L/hour 5, 6, 4.